Scrolling a canvas

Hi
I am tring to scroll a canvas
Here is the code
JScrollPane scrollPane = new JScrollPane(ca, JScrollPane.VERTICAL_SCROLLBAR_ALWAYS, JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
scrollPane.setPreferredSize(new Dimension(500,500));
scrollPane.revalidate();
add(scrollPane, BorderLayout.CENTER);
where ca is the canvas
How do i get the scroll bars to dispaly and move the canvas, presently all is shown is the canvas with blank tracks?
Thanx

yeah it works but i don't want to implement a textArea but a canvas.
The code i have for the canvas is
class Canvas0 extends Canvas{
public Canvas0(){}
int ROOTx = 300;
int ROOTy = 20;
int rootx = 20;
int rooty = 20;
int textx = 275;
int texty = 25;
int KID1x = 250;
int KID1y = 60;
int kid1x = 20;
int kid1y = 20;
int text1x = 225;
int text1y = 65;
int KID2x = 200;
int KID2y = 100;
int kid2x = 20;
int kid2y = 20;
int text2x = 175;
int text2y = 105;
int KID3x = 150;
int KID3y = 140;
int kid3x = 20;
int kid3y = 20;
int text3x = 125;
int text3y = 145;
int LEAFx = 100;
int LEAFy = 180;
int leafx = 20;
int leafy = 20;
int text4x = 75;
int text4y = 185;
     public void paint(Graphics g){
          Font f = new Font("TimesRoman", Font.BOLD, 12);
          String text;
          String text1;
          String text2;
          String text3;
          String leaf;
          g.setFont(f);
          g.drawOval(ROOTx,ROOTy,rootx,rooty);
          g.drawLine(ROOTx+5,ROOTy+5,KID1x+5,KID1y+5);
          text = OViewer.getMain();
          g.drawString(text,textx, texty);
          if(OViewer.getKids1().toString().compareTo("null") != 0){
               System.out.println("111aaaaa");
               g.drawOval(KID1x,KID1y,kid1x,kid1y);
               g.drawLine(KID1x+5,KID1y+5,KID2x+5,KID2y+5);
               KID1x = KID1x + 15;
               KID1y = KID1y + 15;
               text1 = OViewer.getKids1();
               g.drawString(text1,text1x, text1y);
               text1x = text1x+15;
               text1y = text1y+15;
               System.out.println("1111bbbbb");
          while(OViewer.getKids2().toString().compareTo("null") != 0){
               g.drawOval(KID2x,KID2y,kid2x,kid2y);
               g.drawLine(KID2x+5,KID2y+5,KID3x+5,KID3y+5);
               KID2x = KID2x + 15;
               KID2y = KID2y + 15;
               text2 = OViewer.getKids2();
               g.drawString(text2,text2x, text2y);
               text2x = text2x+15;
               text2y = text2y+15;
          while(OViewer.getKids3().toString().compareTo("null") != 0){
               g.drawOval(KID3x,KID3y,kid3x,kid3y);
               g.drawLine(KID3x+5,KID3y+5,LEAFx+5,LEAFy+5);
               KID3x = KID3x + 15;
               KID3y = KID3y + 15;
               text3 = OViewer.getKids3();
               g.drawString(text3,text3x, text3y);
               text3x = text3x+15;
               text3y = text3y+15;
          while(OViewer.getLeaf().toString().compareTo("null") != 0){
               g.drawOval(LEAFx,LEAFy,leafx,leafy);
               LEAFx = LEAFx + 15;
               LEAFy = LEAFy + 15;
               leaf = OViewer.getLeaf();
               g.drawString(leaf,text4x, text4y);
               text4x = text4x+15;
               text4y = text4y+15;
}//end of Canvas0
Is this the problem with the scroll, will i have to use a swing draw facility instead of a java class?

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===========================================
Doc ID: Note:1071311.6
Subject: How to place scrollbars on a tabbed canvas in Forms
Type: PROBLEM
Status: REVIEWED
Content Type: TEXT/PLAIN
Creation Date: 25-MAY-1999
Last Revision Date: 08-JAN-2001
<Note to Author: DO NOT DELETE the following Disclaimer>
This article is being delivered in Draft form and may contain
errors. Please use the MetaLink "Feedback" button to advise
Oracle of any issues related to this article.
Problem Description
===================
How do you place scrollbars on a tabbed canvas in forms?
Solution Description
====================
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===========================================
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